Sawmill dog



March 31, 1953 w. F. cAHooN SAWMILL DOG 3 Sheets-'Sheet l Original Filed Aug. 8, 1949 IN V EN TOR.

'TORNEYS March 3l, 1953 w. F. CAHOON SAWMILL DOG 3 sheets-sheet 5 Y Original Filed Aug. 8, 1949 l INVENTOR. WILL/.4M cnf/00N IBY 107 T ONE YS Patented Mar. 31, 1953 SAWMILL DOG william r'. cannon, Birmingham, Alas. Una Thomas Cahoom executrix of said Williamy F.

Galleon,A deceasedv Original applicationy August 8, 1949, Serial No. 109,131,` now Patent No. 2,626,640, dated Janu ary 27,- 1953. Divided and this application December 15,. 195|), ASerial No. 201.015

4 Claims.

. 1 This is a division of my cci-pending application, serial No. 109,131 med August s. 1949, now Patent No. 2,626,640, and relates to that type of log andlumber clogging apparatus which is operative by iiuid pressure and has for one of its objects the provision of apparatus of the character designated which shall be so constructed, that the weight of al1 the dogging mechanism, except the guide for the dog bar cases and its supporting members is transferred to the center of the head block and' in which the dog cases. dogs, and dog movement cylinders are disposed on the outl` side of the knee, affording accessibility and ease of maintenance. f. Y

A further object of my invention. is to provide clogging apparatus together with improved means for mounting andv moving the dogs inwardly and outward-ly of the dog case, together with improved means for compensating for wear 'between the; dog case and thedog case guide bar.

Still another feature of my invention is the provision' of an improved means for warning the operator whenever the lower dog approaches an unsafe limit of travel forwardly of the dog case. K

Apparatus embodying features of my invention is illustrated in the Aaccompanying, drawings, forming 'ai part oi this application, in which:

Fig. 1 is a side elevationfshowing the forward portion ofQ-jthe knee with the clogging apparatus Figuz isla plan View of the apparatus; y

Fig. 3 'isfa sectional View taken along the line Ill-111 or Fig. 1;

n Fig. `i is a detail view of the upper'dog with the side plate of the dog caseremoved;

Fig. 5 ilsga sectional View taken along-thejline 22 which extends from the top tov bottom ofthe knee. Y

Mounted. on, and vertically movable withrespect to the guide bar, is an upper dog caser 23. The dog case is comprised of two inner side plates 24 and 26 which are spaced apart to straddle the arms I9 and 2|, and permit vertical movement of the case. The plates 24 and 26 are joined together at the top by an operating bracket 21. The outerside of the upper dog case is comprised of two flat spaced bars 28 and 29 and the front and rear by flat bars 3| and 3 2. The front gather at `the yfront by a faceplate I4 .and at the rear byv across member I6. A cylinder support er base plate-l1 extends acrossbetweenthe side plates izan@ 1:3, lad joined tcboth of said plates bywelding or otherwise. A

.in :taehedto the side plate 'i3 of the knee 'is a bracket I8 having an upper' arm` i9"l and a lower arm 2|, towhich issecured a dog case guide'bar and rear bars 3| and 32 are joined to the inner bars 24 and 26 by welding.r and the inner and outer bars are joined together by a suitable number of bolts 33, 34, 36 and 31 which support the upper dog bar guides 38 and 39. They are also joined together by bolts 4|, 42, 43, and 44, which support the intermediate dog bar guides 46 and 41. As shown in Fig. 3 oi the drawing, the dog bar guides are positioned outside, or beyond, the dog case guide bar 22 and thereby do not interfere with the vertical movement of the dog case on the guide bar 22. Mounted within the dog case 23 between the end members 3| and 32, and bearing against the dog case guide bar 22, aregibs 48 and 49. Similar gibs 53 and 54 are mounted alongside the intermediate dog bar guides 46 and 41.. Each of the gibs is provided on its outer side with a pin 58 which fits within a suitable recess in the dog case to hold it in position. The gib 49 may be `adjusted inwardly of the dog case by means of yset screws 5| and 52, and the gib 54 may be similarly adjusted by means of set screws `56 and 5l.

By the means shown, the wear of the guide bar 22 and the gibs may be compensated. Vertical movement of the dog case 23 on the dog case guide bar 22 is limited by means of a stop block 35 which is disposed to engage a pin 40 on theV guide bar at theupper limit of travel of the dog case.

is an upper dog 59 and mounted between the intermediate dog bar guides 46 and 41 is an inter-l mediate dog 6|. yEach of the dogs l59 and 6| is provided with a down turned dogging point 62.

VJoined to each of the dogs 59 and 6| is a rearwardly extending rod 63. A spring 64 surrounds the y.rod 63 and the rod extends rearwardly through a cross head k66 and 'is slidable with re` tion ci the dog. As shown in Fig. 4 of the drawing, the dog bar guides are mounted in the dog Mounted between the dog bar guides `3B and .39'

piston 1s to which is connected a piston rod 14 having the cross head 86 mounted on the outer end thereof. Air is admitted to opposite sides of the piston 13 through conduits 11 and 18 in a manner well understood to cause the piston to move inwardly or outwardly. It will be seen that, with the construction described, in event arlog or other piece of timber comes against the outer end of either of the dogs 59 or 0|, it will be pushed inwardly, compressing the spring 64 against the cross head 06 and thereby preventing damage to the dog. It will also be seen that whateverV the position of the dogs, except when pushed inwardly by timber, the tension on the springs surrounding the dog rods is the same.

The dog case 23 is raised and lowered on the dog case guide bar 22 by means of two air cylinders 19 and 8| which are movably mounted in the knee l between the side walls thereof on the base plate l1. Arubber cushion 82 is interposed between the lower ends of the cylinders and the base plate I1 to cushion movements of the cylinder with respect to the knee. Further description of the means for producing vertical movement of the dog case 23 is not given herein since it forms no part of this application.

Mounted on, and movable vertically with respect to the dog case guide bar 22, is a lower dog case 83. As shown in Fig. 5, the lower dog case is comprised of two spaced parallel steel plates 84 and 86 on the inner side, which are connected to bars 81 and 88 by means of studs 89 and 9|. As shown in Figs. 1 and 2, the bars 81 and 88 eX- tend upwardly and are joined at their upperV ends to an extension 92 on an upper cylinder head 93. The bars 81 and 88 are cylindrical at their upper ends and are threaded as shown to be joinedto the .extension 92 by meansof adjusting nuts 94 and 96 whereby the initial position of the lower dog case with respect to the knee can be varied. As shown in Fig. of the drawing, the bars 84 and 86 overlap the dog case guide bar 22. Joined to the bars 84 and 86 and bearing against the sides of the guide bar 22 are guide blocks, or gibs 91 and 98. Joined to the guide blocks 91 and 98 is an inner guide plate 99. Outer plates |0| and |02 are joined to the plate'99 by a lower spacer block |03, upper dog bar guide |04 and an intermediate dog bar guide |06.

Mounted in the lower dog case just described is a lower dog |01, which, as shown in Fig. 1 is Z- shaped in side elevation so that it bears on the lower spacer block |03 and lies between the intermediate guide |06 and upper guide |04. Secured to the rear end of the dog |01 is a rod |08 having a spring |09 surrounding it in the same manner as the dogs already described. The outer end ofthe rod |08 is threaded and passes through a cross head having a slidable t with respect thereto. VAdjusting nuts 2 and ||3 are screwed onto the outer ends ofthe rod |03 to adjust the initial position of the dog. Also secured to the rear endlV of the dog |01 is -a rod H4 forming a part 0f a safety device to be described in detail hereinafter.v

The lower dog |01 is moved inwardly and outwardly of the dog case 83 Vinto clogging position by means of an air cylinder H6 as. shown in Figs.

l -having a piston rod |22.

4 1 and 5, which is mounted on the lower dog case. The cylinder 6 is secured to the dog case by means of studs ||1 which pass from end to end of the cylinder through heads |I8 and ||9 and into the dog case, on theoutside of the cylinders, and secure the heads ||8 and I9 against separation. Mounted in the cylinder I6 is a piston |2| Secured to the outer ends of the piston rod is the plate, or cross head Il which is slidably connected to the dog rod |08 and bears against. the spring |09. Air is admitted to opposite ends of the cylinder H6, as required, by means of air conduits |23 and |24 in a manner well understood. The conduits |23 and |24 as shown, are relatively long and exible whereby upon separation of the upper and lower dog cases, the air connections are not broken.

Referring now to Fig. 6, together with Fig. 1, Ishow in detail the construction and operation of the lower dog safety limit device. The rod ||4 is connectedto a movable cross head |25 which has connected thereto and extending forwardly therefrom a rectangular bar |21. The bar |21 fits slidingly within a guide |28 secured to the side ofthe knee at the rear thereof. At |29, is indicated a tapering mechanism mounted on the knee which forms no part of my present invention. Accordingly itis not described in detail. Extending outwardly from the cross head |26 is abracket. |3| which moves forwardly and rearwardly with the cross head. Mounted `on the head block is a valve case |32 having a plunger |33 extending rearwardly therefrom in the path of movement of the bracket I3 A set screw |34 extends, through the bracket i3| to engage the stem |33. .Air is -admittedtothe housing |32 by meansjof a conduit |36 and, upon opening of the valve by means of the valve stern |33 escapes through a conduit |31. When this occurs, a whistle |38, connected to the conduit |31 is blown to warn the operator that the lower dog has reached the safe outward limit'of its travel. Also, when this occurs, the bracket |3| engages the housing |32 and further forward movement of the lower dog is prevented. While I have shown an air operated cylinder and a whistle as the warning signal it will b e obvious however that other well known forms of warning signal may be employed. f .j i

From the foregoing description, the operation of my improved dog'ging apparatus willubeA readily understood. With a piece of timber .placed againstthe face plate 4 of thefknee between the lower'dog |01 and one of the dogs 59,01' s i, as the case may be, depending upon the thickness of the timber, the dogsare movedv forwardly, if necessary, to dogging position. whereby they can engage the timber.v With the dogs in position to engage V,the timber, air-is admitted to theupper ends of the cylinder`s'19and Si to force the pistons downwardly carrying with them Ythe bracket 21 and dog case 23 to lower the dogs 59 and 6|. Assoon as the'dog 59 o r 0l. as the case may be,` engages the timber', its further downward movement' is arrested and the action of the air against the upper endso' the cylinders 19 and 8|, raises the "cylinders oi their support carrying withvthem the extensionsv 9 2", the lower dog case lift bars 81 and Stand th lowerdog case 83,` thereby to raise the lcwer'dog |01. to engage the .lower side of the timber. When vitis desired to release the timber, or move the dogs to anotherposition, air isa'dmitte'd to the` lower ends of'A thecylinders 19 and 8|=where upon the. pistons -move upwardly, takingthe bracket-21 and dog-case 2.3,and disengagingfthe centrally of the knee. f by the knee and laterally thereof is the weight upper dogs from the timber. At the same time the lower dog |01 is released from the timber.

From the foregoing, it will be seen that with the cylinders 79 and 8| located between the side walls of the knee, and the dog cases and dogs supported from the cylinders, that all the weight of the apparatus is transferred to the head block The only weight carried of the dog case guide bar 22. The positioning of the upper and lower dog cases outside the knee renders them readily accessible for adjustment and maintenance which is a very important item in the operation of a sawmill. Itwill thus be seen that I have provided improved clogging apparatus which is simple and sturdy of construction, and which is readily adjusted and maintained. Y

While I have shown my invention in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications, without departing ffrom the spirit thereof, and I desire, therefore, that only such limitations shall be Y placed thereupon as are specifically set forth in the appended claims.

What I claim is:

1. In timber dogging apparatus, a dog case, a dog mounted in the case for rectilinear movement forwardly and rearwardly thereof in a substantially horizontal plane, a pneumatic cylinder mounted in the case alongside the dog and having a piston therein with a piston rod movable outwardly and inwardly of the cylinder in a substantially horizontal plane, a cross head mounted rigidly onthe piston rod extending laterally therefrom to the rear of the dog, a rod on the dog extending rearwardly therefrom through the cross head and positioned outwardly of the dog case, there being an opening in the cross head in which the rod slidingly fits, a spring surrounding the rod between the cross head and the dogV and biasing the dog outwardly of said dog case, and adjusting nuts on the rear end of the rod for` varying the innermost position of the dog with respect to the dog case.

2. In timber clogging apparatus, a hollow knee, a vertically extending dog case guide bar supported from and positioned on the outside of the knee, a dog case slidably mounted for vertical movement on the dog case guide bar and comprising inner and outer side walls, a dog mounted for rectilinear movement in the dog case to move forwardly and rearwardly therein in a substantially horizontal plane, horizontally extending dog guide bars mounted in the dog case outwardly of said dog case guide bar, and

means to adjust vertically the position of the dog guide bars in the dog case.

3. In timber dogging apparatus, a dog case, a dog mounted in the case for rectilinear movement forwardly and rearwardly thereof in a. substantially horizontal plane, a pneumatic cylinder mounted in the case alongside the dog and having a piston therein with a piston rod movable outwardly and inwardly of the cylinder in a'sub stantially horizontal plane, a cross head mounted rigidly on the piston rod extending laterally therefrom to the rear of the dog, a rod on the dog extending rearwardly therefrom passing slidably through the cross head and positioned outwardly of the dog case, a spring surrounding the rod between the cross head and the dog and biasing the dog outwardly of said dog case, and a stop for said cross head on the rear end of said rod.

4. In timber dogging apparatus, a hollow knee, a vertically extending dog case guide barV supported from and positioned on the outside of the knee, a dog case slidably mounted for vertical movement on the dog case guide bar and comprising side walls and end members, a dog mounted for rectilinear motion in the dog case and adapted to move forwardly and rearwardly therein in a substantially horizontal plane, horizontally extending dog guide bars mounted in the dog case outwardly of said dog case guide bar, means to adjust vertically the position of the dog guide bars in the dog case and adjusting means interposed between said dog case guide bar and said end members adapted to movesaid dog case horizontally with respect to said dog case guide bar.

WILLIAM F. CAHOON.

REFERENCES CITED The following references are of record in the le of thisk patent:

UNITED STATES PATENTS 

